1. Field of the Invention
The present invention relates to imaging devices and electronic viewfinder display methods and, in particular, to an imaging device and electronic viewfinder display method capable of switching between an electronic viewfinder and an optical viewfinder.
2. Description of the Related Art
In the technical field of digital cameras (imaging devices) so far, it is general that an electronic image of a subject obtained from an imaging lens an imaging optical system such as an image pickup element is displayed on a liquid-crystal monitor to check composition and a focus state. However, in recent years, models provided with a finder for checking composition and a focus state separately from a liquid-crystal monitor on a rear surface have been widespread. As these finder types, there are an optical viewfinder (OVF: Optical View Finder, hereinafter OVF) and an electronic viewfinder (EVF: Electronic View Finder, hereinafter EVF), which each have advantages and disadvantages.
Specifically, the OVF has some superiority over the EVF, such as “no response delay in display”, “clear display image”, and “composition can be easily determined since the outside of an imaging range can be viewed (depending on the type)”. On the other hand, the EVF has superiorities in use over the OVF, such as “replayed image and menu display (including superimposing display) are possible”. Therefore, in a digital camera (imaging device) including both an OVF and an EVF, it is preferable to switch between the OVF and the EVF as appropriate according to the situation.
Imaging devices including an electronic viewfinder are described in, for example, Japanese Patent Application Laid-Open No. 2010-16610 (hereinafter referrred to as PTL 1) and Japanese Patent Application Laid-Open No. 2010-119029 (hereinafter referrred to as PTL 2). PTL 1 discloses an imaging device including a finder device allowing simultaneous observation of a first display region and a second display region from an ocular window through an optical system, the first display region in which a subject image is observed as an optical image and the second display region in which an electronic image obtained by photoelectric conversion by the image pickup element and displayed by a display device is observed; and the imaging device also including a display control device which distorts the electronic image in advance by image processing so that luminous distortion occurring due to passage through the optical system when observed from the ocular window is cancelled out for display on the display device.
With this, while observation of an optical image of a substance is kept possible without taking eyes off the finder, the state of an image taken, the state of settings of the camera, and imaging auxiliary information can be checked with the electronic image. Furthermore, since the electronic image is subjected to image processing in advance so that distortion occurring due to passage through the finder optical system is inconspicuous, the electronic image to be observed becomes a favorable image with distortion cancelled out.
Furthermore, PTL 2 discloses an imaging device including an imaging device which images a subject via an imaging optical system and outputs an image signal, an image processing device which generates image data based on the image signal, a first display device which displays an image based on the image data, and a visual recognition optical system allowing visual recognition of the image, wherein the image processing device generates image data so as to correct optical aberration of the visual recognition optical system.
With this, an imaging device can be provided capable of electrically correcting optical aberration such as magnification chromatic aberration and distortion aberration due to a loupe lens of an electronic-type viewfinder and allowing observation of a subject image without color bleeding, distortion and so on.